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2.
PLoS One ; 16(11): e0259299, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34818338

RESUMO

Accurate maps of species ranges are essential to inform conservation, but time-consuming to produce and update. Given the pace of change of knowledge about species distributions and shifts in ranges under climate change and land use, a need exists for timely mapping approaches that enable batch processing employing widely available data. We develop a systematic approach of batch-processing range maps and derived Area of Habitat maps for terrestrial bird species with published ranges below 125,000 km2 in Central and South America. (Area of Habitat is the habitat available to a species within its range.) We combine existing range maps with the rapidly expanding crowd-sourced eBird data of presences and absences from frequently surveyed locations, plus readily accessible, high resolution satellite data on forest cover and elevation to map the Area of Habitat available to each species. Users can interrogate the maps produced to see details of the observations that contributed to the ranges. Previous estimates of Areas of Habitat were constrained within the published ranges and thus were, by definition, smaller-typically about 30%. This reflects how little habitat within suitable elevation ranges exists within the published ranges. Our results show that on average, Areas of Habitat are 12% larger than published ranges, reflecting the often-considerable extent that eBird records expand the known distributions of species. Interestingly, there are substantial differences between threatened and non-threatened species. Some 40% of Critically Endangered, 43% of Endangered, and 55% of Vulnerable species have Areas of Habitat larger than their published ranges, compared with 31% for Near Threatened and Least Concern species. The important finding for conservation is that threatened species are generally more widespread than previously estimated.


Assuntos
Aves , Espécies em Perigo de Extinção , Sistemas de Informação Geográfica , Animais , Crowdsourcing
3.
Ecol Lett ; 24(4): 819-828, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33594778

RESUMO

For migratory species, seasonal movements complicate local climate adaptation, as it is unclear whether individuals track climate niches across the annual cycle. In the migratory songbird yellow warbler (Setophaga petechia), we find a correlation between individual-level wintering and breeding precipitation, but not temperature. Birds wintering in the driest regions of the Neotropics breed in the driest regions of North America. Individuals from drier regions also possess distinct morphologies and population responses to varying rainfall. We find a positive association between bill size and breeding season precipitation which, given documented climate-associated genomic variation, might reflect adaptation to local precipitation regimes. Relative abundance in the breeding range is linked to interannual fluctuations in precipitation, but the directionality of this response varies across geography. Together, our results suggest that variation in climate optima may exist across the breeding range of yellow warblers and provide a mechanism for selection across the annual cycle.


Assuntos
Migração Animal , Mudança Climática , Animais , Clima , Variação Genética , Humanos , América do Norte , Estações do Ano
4.
Conserv Biol ; 35(5): 1388-1395, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33484006

RESUMO

Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision-making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid-response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human-induced extinctions is imperative given the irreversibility of species loss.


Asignación de Recursos para la Conservación, Resiliencia de Poblaciones Pequeñas y la Falacia del Triaje de Conservación Resumen Algunos métodos de priorización de la conservación están basados en el supuesto de que las necesidades de la conservación superan a los actuales recursos y que no todas las especies pueden ser conservadas; por lo tanto, se necesita un esquema de triaje (esto es, cuando el sistema está abrumado, las especies deben dividirse en tres grupos con base en su probabilidad de supervivencia y los esfuerzos deben enfocarse en aquellas especies dentro del grupo con las mejores probabilidades de supervivencia y a aquellas en el grupo sin probabilidades de supervivencia o aquellas en el grupo que no necesita esfuerzos especializados para su conservación se les deben reducir o negar los esfuerzos de conservación) para dirigir la asignación de recursos. Discutimos que esta estrategia para la toma de decisiones no es apropiada porque los recursos no están tan limitados como se asume con frecuencia y tampoco es evidente que existan especies que no puedan ser conservadas. Por ejemplo, tan sólo un tamaño poblacional pequeño no es suficiente para condenar a una especie a la extinción; contamos con ejemplos en plantas, reptiles, aves y mamíferos. Aunque actualmente todos los recursos dedicados a la conservación de todas las especies amenazadas son insuficientes, los recursos económicos mundiales son vastos y se podrían dedicar mayores recursos a la conservación de especies. El marco de trabajo político para la conservación de especies ha mejorado, con iniciativas como los Objetivos de Desarrollo Sustentable de la ONU y otros acuerdos internacionales, el financiamiento de mecanismos como el Fondo para el Medio Ambiente Mundial, y el surgimiento de muchas organizaciones no gubernamentales mediante programas de subsidios pequeños hábiles y de respuesta rápida. Para que un sistema de priorización no permita las extinciones, las cero extinciones deben ser un objetivo explícito del sistema. La extinción no es inevitable y no debería ser aceptable. El objetivo de cero extinciones inducidas por humanos es imperativo dada la irreversibilidad de la pérdida de especies.


Assuntos
Conservação dos Recursos Naturais , Triagem , Animais , Biodiversidade , Espécies em Perigo de Extinção , Extinção Biológica , Mamíferos , Alocação de Recursos
6.
Science ; 338(6109): 946-9, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23065904

RESUMO

World governments have committed to halting human-induced extinctions and safeguarding important sites for biodiversity by 2020, but the financial costs of meeting these targets are largely unknown. We estimate the cost of reducing the extinction risk of all globally threatened bird species (by ≥1 International Union for Conservation of Nature Red List category) to be U.S. $0.875 to $1.23 billion annually over the next decade, of which 12% is currently funded. Incorporating threatened nonavian species increases this total to U.S. $3.41 to $4.76 billion annually. We estimate that protecting and effectively managing all terrestrial sites of global avian conservation significance (11,731 Important Bird Areas) would cost U.S. $65.1 billion annually. Adding sites for other taxa increases this to U.S. $76.1 billion annually. Meeting these targets will require conservation funding to increase by at least an order of magnitude.


Assuntos
Biodiversidade , Aves , Financiamento de Capital , Conservação dos Recursos Naturais/economia , Extinção Biológica , Animais , Custos e Análise de Custo , Humanos
7.
Acta Crystallogr C ; 63(Pt 12): o685-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18057613

RESUMO

In the title compounds, 2-methoxyethyl 6-amino-5-cyano-2-methyl-4-(1-naphthyl)-4H-pyran-3-carboxylate, C21H20N2O4, (II), isopropyl 6-amino-5-cyano-2-methyl-4-(1-naphthyl)-4H-pyran-3-carboxylate, C21H20N2O3, (III), and ethyl 6-amino-5-cyano-2-methyl-4-(1-naphthyl)-4H-pyran-3-carboxylate, C20H18N2O3, (IV), the heterocyclic pyran ring adopts a flattened boat conformation. In (II) and (III), the carbonyl group and a double bond of the heterocyclic ring are mutually anti, but in (IV) they are mutually syn. The ester O atoms in (II) and (III) and the carbonyl O atom in (IV) participate in intramolecular C-H...O contacts to form six-membered rings. The dihedral angles between the naphthalene substituent and the closest four atoms of the heterocyclic ring are 73.3 (1), 71.0 (1) and 74.3 (1) degrees for (II)-(IV), respectively. In all three structures, only one H atom of the NH2 group takes part in N-H...O [in (II) and (III)] or N-H...N [in (IV)] intermolecular hydrogen bonds, and chains [in (II) and (III)] or dimers [in (IV)] are formed. In (II), weak intermolecular C-H...O and C-H...N hydrogen bonds, and in (III) intermolecular C-H...O hydrogen bonds link the chains into ladders along the a axis.


Assuntos
Ésteres/síntese química , Piranos/química , Cristalografia por Raios X , Dimerização , Ésteres/química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Piranos/síntese química
8.
Acta Crystallogr C ; 62(Pt 12): o705-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17148918

RESUMO

The syntheses, X-ray structural investigations and calculations of the conformational preferences of the carbonyl substituent with respect to the pyran ring have been carried out for the two title compounds, viz. C15H14N2O2, (II), and C20H16N2O2.C2H3N, (III), respectively. In both molecules, the heterocyclic ring adopts a flattened boat conformation. In (II), the carbonyl group and a double bond of the heterocyclic ring are syn, but in (III) they are anti. The carbonyl group forms a short contact with a methyl group H atom in (II). The dihedral angles between the pseudo-axial phenyl substituent and the flat part of the pyran ring are 92.7 (1) and 93.2 (1) degrees in (II) and (III), respectively. In the crystal structure of (II), intermolecular N-H...N and N-H...O hydrogen bonds link the molecules into a sheet along the (103) plane, while in (III), they link the molecules into ribbons along the a axis.


Assuntos
Nitrilas/química , Piranos/química , Algoritmos , Cristalografia por Raios X , Estrutura Molecular , Solubilidade
9.
Acta Crystallogr C ; 61(Pt 12): o741-4, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16330864

RESUMO

Calculations of the conformational preferences of the methoxyphenyl substituent with respect to the pyran ring have been carried out for the two title compounds, C19H20N2O3, (II), and C18H20N2O5.0.5H2O, (III). In both molecules, the heterocyclic ring adopts a flattened boat conformation and the fused cyclohexenone ring adopts a 'sofa' conformation. The dihedral angles between these two flat fragments are 14.5 (1) and 9.3 (1) degrees in (II) and (III), respectively. In both molecules, the methoxy group of the pseudo-axial aryl substituent is syn with respect to the pyran ring. The dihedral angles between the 2-methoxyphenyl rings and the flat parts of the pyran rings are 86.3 (1) and 87.0 (1) degrees, respectively. In the crystal structure of (II), intermolecular N-H...N and N-H...O hydrogen bonds link molecules into a three-dimensional framework. In the crystal structure of (III), a strong intramolecular N-H...O hydrogen bond links the flat conjugated H-N-C=C-N-O fragment into a six-membered ring. In (III), the water molecule lies on a twofold axis and forms bifurcated O-H...O hydrogen bonds with the NO2 group of the molecule. Also in (III), hydrogen bonds link the organic and water molecules into infinite tapes along the c axis.


Assuntos
Benzopiranos/química , Nitrilas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
11.
Acta Crystallogr C ; 60(Pt 7): o536-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15237190

RESUMO

The title compounds, 1-chloro-3,6-dimethoxy-2,5-dimethylbenzene, (IIIa), and 1-chloro-3,6-dimethoxy-2,4-dimethylbenzene, (IIIb), both C10H13ClO2, were obtained from 2,5- and 2,6-dimethyl-1,4-benzoquinone, respectively, and are intermediates in the synthesis of ammonium quinone derivatives. The isomers have different substituents around the methoxy groups and crystallize in different space groups. In both molecules, the methoxy groups each have different orientations with respect to the benzene ring. In both cases, one methoxy group lies in the plane of the ring and can participate in conjugation with the aromatic system, while the second is almost perpendicular to the plane of the aromatic ring. The C-O-C bond angles around these substituents are also different: 117.5 (4) and 118.2 (3) degrees in (IIIa) and (IIIb), respectively, when the methoxy groups lie in the plane of the ring, and 114.7 (3) and 113.6 (3) degrees in (IIIa) and (IIIb), respectively, when they are out of the plane of the ring.


Assuntos
Hidrocarbonetos Clorados/química , Xilenos/química , Cristalografia por Raios X , Isomerismo , Conformação Molecular
12.
Acta Crystallogr C ; 60(Pt 5): o334-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15131384

RESUMO

Syntheses and X-ray structural investigations have been carried out for the two title compounds, C(20)H(16)N(2)O(2), (IIIa), and C(22)H(20)N(2)O(2), (IIIb). In (IIIa), the heterocyclic ring adopts a sofa conformation, while in (IIIb), the ring has a flattened boat conformation. In both molecules, the fused cyclohexenone ring adopts a sofa conformation. The dihedral angles between these two flat fragments are 3.5 (2) and 17.5 (2) degrees in (IIIa) and (IIIb), respectively. The dihedral angles between the pseudo-axial naphthalene substituents and the planes of the pyran rings are 90.9 (1) and 96.7 (1) degrees, respectively. In the crystal structure of (IIIa), intermolecular N-H.N and N-H...O hydrogen bonds link the molecules into infinite tapes along the b axis, while molecules of (IIIb) form centrosymmetric dimers via N-H...N hydrogen bonds, with only one H atom of the NH(2) donor group taking part in hydrogen bonding.

13.
Acta Crystallogr C ; 59(Pt 12): o700-2, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14671375

RESUMO

Bis(2,5-dimethoxy-4-methylphenyl)methane, C(19)H(24)O(4), (IIa), was obtained and characterized as a minor product from the reaction of toluhydroquinone dimethyl ether (1,4-dimethoxy-2-methylbenzene) with N-(hydroxymethyl)trifluoroacetamide. Similarly, bis(2,5-dimethoxy-3,4,6-trimethylphenyl)methane, C(23)H(32)O(4), (IIb), was prepared from the corresponding reaction of trimethylhydroquinone dimethyl ether (2,5-dimethoxy-1,3,4-trimethylbenzene). The molecules of (IIa) and (IIb) each lie on a twofold axis passing through the methylene group. The dihedral angle between the planar phenyl rings is 73.4 (1) degrees in (IIa) and 77.9 (1) degrees in (IIb). The external bond angles around the bridging methylene group are 116.6 (2) and 117.3 (2) degrees for (IIa) and (IIb), respectively. In (IIa), the methoxy substituents lie in the plane of the ring and are conjugated with the aromatic system, whereas in (IIb), they are almost perpendicular to the phenyl ring and are positioned on opposite sides.


Assuntos
Anisóis/química , Compostos Benzidrílicos/química , Carbono , Cromatografia , Cristalografia por Raios X , Hidrogênio , Hidroquinonas/química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Modelos Moleculares
14.
J Steroid Biochem Mol Biol ; 84(4): 431-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12732288

RESUMO

Estrogen is the natural agonist of the estrogen receptor (ER). However, certain plant-derived compounds or phytoestrogens have been identified that mimic estrogens and act as agonists and/or antagonists of ERs, depending on subtype and target tissue. Using thin layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS), and proton nuclear magnetic resonance (1H-NMR), we identified a simple phenol, 4-ethoxymethylphenol (4EM), found in Maclura pomifera that acts as an agonist of ER-alpha and ER-beta in HeLa and MCF-7 cells. To study the effect of 4EM on ER-alpha and ER-beta activity, we performed transient transfection assays and showed that 4EM activated ER-dependent gene transcription in a dose-dependent manner on both ER subtypes and this activity was inhibited by trans-4-hydroxytamoxifen (4HT). Further, 4EM-mediated transcription in ER-alpha, like estrogen, was enhanced in the presence of coactivators, steroid receptor coactivator-1 (SRC-1), CREB binding proteins (CBP), and E6-associated protein (E6-AP). We found that 4EM was specific for ER and did not activate transcription of the progesterone receptor.


Assuntos
Estrogênios não Esteroides/química , Estrogênios não Esteroides/farmacologia , Isoflavonas , Fenóis/química , Fenóis/farmacologia , Receptores de Estrogênio/agonistas , Tamoxifeno/análogos & derivados , Ligação Competitiva , Proteína de Ligação a CREB , Cromatografia em Camada Fina , Relação Dose-Resposta a Droga , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Cromatografia Gasosa-Espectrometria de Massas , Genes Reporter , Células HeLa , Humanos , Ligases/metabolismo , Maclura/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Químicos , Proteínas Nucleares/metabolismo , Fitoestrógenos , Preparações de Plantas , Plasmídeos/metabolismo , Ligação Proteica , Receptores de Progesterona/metabolismo , Proteínas Recombinantes/metabolismo , Tamoxifeno/farmacologia , Transativadores/metabolismo , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases
15.
Mol Ecol ; 12(3): 675-83, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12675823

RESUMO

As a result of recurrent droughts and anthropogenic factors, the range of the lesser prairie-chicken (Tympanuchus pallidicinctus) has contracted by 92% and the population has been reduced by approximately 97% in the past century, resulting in the smallest population size and most restricted geographical distribution of any North American grouse. We examined genetic variation through DNA sequence analysis of 478 base pairs of the mitochondrial genome and by assaying allelic variation at five microsatellite loci from lesser prairie-chickens collected on 20 leks in western Oklahoma and east-central New Mexico. Traditional population genetic analyses indicate that lesser prairie-chickens maintain high levels of genetic variation at both nuclear and mitochondrial loci. Although some genetic structuring among lesser prairie-chicken leks was detected within Oklahoma and New Mexico for both nuclear and mitochondrial loci, high levels of differentiation were detected between Oklahoma and New Mexico populations. Nested-clade analysis of mitochondrial haplotypes revealed that both historic and contemporary processes have influenced patterns of haplotype distributions and that historic processes have most likely led to the level of differentiation found between the Oklahoma and New Mexico populations.


Assuntos
Galinhas/genética , Alelos , Animais , Conservação dos Recursos Naturais , DNA/química , DNA/genética , Variação Genética , Repetições de Microssatélites/genética , New Mexico , Oklahoma , Filogenia , Reação em Cadeia da Polimerase/veterinária , Alinhamento de Sequência , Análise de Sequência de DNA
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